Regarding NSVT or VT

Dear Doctor, Happy Holidays.
I am curious regarding recent posts on NSVT.  Here are my questions:

1)  What would NSVT feel like if one were taking a peripheral pulse when it was occurring- Would it feel like a tachycardia (since people talk of rates in the 100's) or since its defined as 3-4 PVC's in a row, would it just feel like several skipped beats in a row?

2) Are there generally physical symptoms to go along with it i.e. low or high BP, SOB, dizziness, etc.?

Following a recent EP Study my EP said he could not elicit any dangerous ventricular arrythmias

3) How do you Docs check for that during an EP Study? (My doctor said he could not induce any ventricular arythmias-but I swear I have PVC's sometimes)

4) I know that with the heart there are no absolutes, but if this potentially dangerous arrythmia could not be induced during the study, How likely would it be that it could occur anyway?

Thankyou in advance for your answers.

[Michael J. McWilliams, M.D.]

1)  What would NSVT feel like if one were taking a peripheral pulse
Would it feel like a tachycardia (since people talk of rates in the 100's) or since its defined as 3-4 PVC's in a row, would it just feel like several skipped beats in a row?

It would feel like very rapid beats.  The strength of your pulse is likely to diminish during those beats because blood pressure will usually decrease.  It might feel like a long episode PVCs if you feel your PVCs.


2) Are there generally physical symptoms to go along with it i.e. low or high BP, SOB, dizziness etc.?

Many people do not feel them.  For those that do, they often describe feeling fast beats, skipped beats associated with a second or two of lightheadedness.

3) How do you Docs check for that during an EP Study? (My doctor said he could not induce any ventricular arrhythmias-but I swear I have PVC's sometimes)

During an EP study with pace the heart from the atrium and from the ventricle.  We pace a given rate and then start to add in PVCs at progressively shorter intervals.  Then we will add two and then three PVCs at progressively shorter intervals.  If you are having an EP study done for this reason, I am guess your heart function is greater than 35% otherwise a defibrillator would be placed.  In an EP study, it does not matter if you have PVCs because PVCs are not considered a dangerous arrhythmia.  EP studies are done to try and induce sustained arrhythmias.  Your doctor was probably trying to determine if there was an arrhythmia that was not being picked up by the holter.  In all likelihood, you do have PVCs but that is not what he test is looking for.


4) I know that with the heart there are no absolutes, but if this potentially dangerous arrythmia could not be induced during the study, How likely would it be that it could occur anyway?

If you aren't in a high risk group -- EF less than 35%, known genetic disorder that predisposes you to sudden death or previous aborted sudden death, your risk of sudden cardiac death should be about the same as an age matched population.  In general, the risk of sudden death for people over the age of 40 is about 1/1000 with the for people that are 40 years old being less than 1/1000 and people that are much older being greater than 1/1000.

If your EP has done an EP study, echo and EKG and you do not have high risk features, your risk should be very low.

I hope this helps.  Thanks for posting.